I found a game called Dark Cloud in one of these demo disks. Still today is one of my favorite games. Unfortunately is not very known due to bad marketing.
It depends a lot by the style and the trainer. I was training Go-Ju style Karate for 9 years and had a positive experience, while I had a negative one with a different style years before. All martial arts has a lot of different styles that can be very different between them.
In my opinion the important thing is to find a school that doesn't have too much people and where she can be actively followed by the trainer.
Then, it also depends if you are looking for a sport/competitive experience or something more traditional. In my case we were training it as a martial art and went rarely to competitions.
I found a game called Dark Cloud in one of these demo disks. Still today is one of my favorite games. Unfortunately is not very known due to bad marketing.